Is there any tablet/large phone that can pair with another phone via bluetooth as a headset?

I'm looking to replicate a car's navigation system with my android phone and tablet. What I want to do is use a tablet (7" or so) or a large phone without service (i.e. Galaxy Note) to mount to my older car's dash so I can use my GPS app (doesn't require data) but also when I get a call to the phone in my pocket, the screen indicates as such and lets me press a button to answer and start talking...just like a phone's nav system does.